Add scheduling, machine info, caching strategies and devices (#9)

Reviewed-on: Rubydragon/MetagraphOptimization.jl#9
Co-authored-by: Anton Reinhard <anton.reinhard@proton.me>
Co-committed-by: Anton Reinhard <anton.reinhard@proton.me>

src/task/create.jl

@@ -3,8 +3,7 @@
 
 Fallback implementation of the copy of an abstract data task, throwing an error.
 """
-copy(t::AbstractDataTask) =
-    error("Need to implement copying for your data tasks!")
+copy(t::AbstractDataTask) = error("Need to implement copying for your data tasks!")
 
 """
     copy(t::AbstractComputeTask)
@@ -12,3 +11,21 @@ copy(t::AbstractDataTask) =
 Return a copy of the given compute task.
 """
 copy(t::AbstractComputeTask) = typeof(t)()
+
+"""
+    copy(t::FusedComputeTask)
+
+Return a copy of th egiven [`FusedComputeTask`](@ref).
+"""
+function copy(t::FusedComputeTask{T1, T2}) where {T1, T2}
+    return FusedComputeTask{T1, T2}(
+        copy(t.first_task),
+        copy(t.second_task),
+        copy(t.t1_inputs),
+        t.t1_output,
+        copy(t.t2_inputs),
+    )
+end
+
+FusedComputeTask{T1, T2}(t1_inputs::Vector{String}, t1_output::String, t2_inputs::Vector{String}) where {T1, T2} =
+    FusedComputeTask{T1, T2}(T1(), T2(), t1_inputs, t1_output, t2_inputs)